Reversals of Established Medical PracticesEvidence to Abandon Ship

Author Affiliations: Department of Medicine, Northwestern University, Chicago, Illinois (Dr Prasad); Department of Medicine, University of Chicago, Chicago (Dr Cifu); and Stanford Prevention Research Center and Departments of Medicine and Health Research and Policy, Stanford University School of Medicine, Stanford, California (Dr Ioannidis).

Ideally, good medical practices are replaced by better ones, based on robust comparative trials in which new interventions outperform older ones and establish new standards of care. Often, however, established standards must be abandoned not because a better replacement has been identified but simply because what was thought to be beneficial was not. In these cases, it becomes apparent that clinicians, encouraged by professional societies and guidelines, have been using medications, procedures, or preventive measures in vain. For example, percutaneous coronary intervention performed for stable coronary artery disease and hormone therapy prescribed for postmenopausal women cost billions of dollars and supported the existence of entire specialties for many years. Stable coronary artery disease accounted for 85% of all stenting in the United States at the time of the Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) trial.1 Large, well-designed randomized trials that tested whether these practices improved major patient outcomes revealed that patients were not being helped. Defenders of these therapies and interventions wrote rebuttals and editorials and fought for their specialties, but the reality was that the best that could be done was to abandon ship.